Well pipe plug



Oct. 15, 1940. G. s; KNOX WELL PIPE PLUG Filed April 29, 1940 4 Sheets-Sheet l Oct. 15, 1940. G. s. KNOX 2,217,986

WELL PIPE PLUG Filed April 29, 1940 4 Sheets-Sheet 2 G. SA KNOX WELL PIPE PLUG Oct. l5, 1940.

Filed April 29, 1940 4 Sheets-Sheet 3 w V l. /wd 9. 2

Oct.- l5, 1940. v Q '5. KNOX 2,217,986 WELL PIPE PLUG Filed April 29, 1940 4 Sheets-Sheet 4 @la J4 Patented Och-15, 1940 UNITED STATES WELL PIPE PLUG Granville S. Knox, Los Angeles, Calif., assignor poration oi' Nevada vto Hydril Company, Los Angeles, Calif., a cor- Application April 29, 1940, Serial N0. 332,231

l 26 Claims. (Cl. 16S-13) This invention relates generally to well pipe or casing plugs of the type adapted to be lowered into a well on a suspension means and set at any desired depth within the well pipe for seal-I ing oi fluid pressures from below. Certain aspects of the invention contemplate improvements in the type of plug disclosed in my copending application, Ser. No. 150,569, filed Jun'e 26, 1937, on Well pipe plug, now Patent No. 2,205,748,

1 granted June 25, 1940.

The plug here described is of the retrievable" type, that is, after once being set it may be released and withdrawn `from the well Apipe, in contra-distinction to plugs of the non-retrievable 1* type which either are left in place permanently f or are drilled out and thus destroyed in the event it is desired to unplug the well.

.A retrievable plug lis used, in the main, as a temporary plugging means to enable the operator to change surface fittings or to carry on other operations which require the shutting oi ofpresf sures at some lower point in the well pipe. Such plugs are seldom made of readily drillable material and, in any event, they are used primarily in well producing operations after all drilling equipment has been dismantled or removed from the well.

It follows that it is of utmost importance that the retrievable type of plug be readily and surely releasable from the wellv pipe after it has served its purpose, for a single failure has often resulted in tremendous loss of time and money due not only to the expense of setting' up and operating heavy drilling or well pulling equipment, but also to the loss of producion which results from tying up the well.

It is' therefore among the objects of my invention to provide a retrievable plug which not only serves its plugging purposes exceptionally well,

4,0 but that can readily and surelybe withdrawn when the time for that operation arrives.

And the invention fullls the further object of providing a plug which may be surely and readily released even though the plug may be 4" submerged in sand and debris, with such foreign matter having the natural tendency to lodge between working parts and thus interfere with their.

proper operation. How ,the device works even under the most .disadvantageous conditions, how

50 the resistance of the sand or other material is overcorna'and how such foreign matter may be dislodged from between workingparts, especially when the plug is used as a bottom hole choke,

will be made apparent in the detailed description.

" In their general construction, plugs of this type to a body or slip carrier section of the plug so comprise a tubular mandrel carrying expansible pipe gripping means and a packenboth adapted to -be broughtinto tight engagement with the well pipe by vertical movement of the mandrel. Fluid flow through the mandrel may be controlled by a valve which, preferably,A also is adapted to be opened and closed by operation of the mandrel. One of the principal features of the invention is the provision of means wherebyv the pipe gripping means, packer and valve may 1 be operated in predetermined sequence by exerting a straight upward pull on the suspension means, thus permitting the plug to be run into the well and operated on a wireline or cable.

The invention has another outstanding feature l5 of importance in the use of a locking mechanism operating after expansion of the packer and gripping means to'hold the mandrel in its corresponding position, and releasable to cause contraction of the gripping means 'and packerand permit removal of the plug from the pipe. I provide in conjunction with the locking mechanism a setting tool releasably connected to the mandrel so as to be removable after the plug is set. In accordance with the invention,l the setting tool is associated with the mandrel and locklng mechanism in a manner such that the setting tool is not releasable from the mandrel until the latter has become locked in its packer expanding position, but is/ then disconnectible by continued straight upward pull on the suspension means.v Thus ini operating sequence, sustained pull on Athe suspension means first raises the mandrel to set the slips and packer, then actuates the locking mechanism to hold the mandrel in raised position,

and finally causes the setting tool to be released from the plug.

' The plug is removable from the well by lowering a retrieving tool adapted to be` brought into engagement with the mandrel and jarred downwardly to release the mandrel from the locking mechanism and permit the gripping means and packer to contract. The retrieving-tool attaches as to permit the plug to be removed from lthe pipe bythe retrieving tool, with the gripping means and packer maintained in contracted' positions.

Or the plug may be adjusted to a new depth and resetthis in spite of the fact that the sus- 50 pension means is in the form of a flexible cable. This feature is particularly valuable in 'eonnecy tion with the use of a plug for locating leaks in a Well pipe, where the plug is successively set and the pipe tested at spaced intervals down the pipe. n

Because of the sometimes extreme dlerential4 in pressures above and below -the plug, it becomes diilicult in the usual plug to set up the relative movement between body and mandrel sections required to disengage the pipe-gripping means and packer from the pipe wall. I overcome this diflculty by providing means for opening a valve of relatively small area, as compared to the crosssectional area of the plug body and hence of the well-pipe, which allows the pressures above and below the plug to become balanced and thus relieve the Wedging force which the initially predominant upward pressure exerts against the pipe gripping and sealing means.

The releasable locking means between setting or retrieving tool and the plug is of a nature to prevent accidental disconnection even under such conditions as when the plug has to be jarred downwardly through Wax deposits or scale in .the well pipe.

The invention embodies various additional features and novel structural details, but these will all be understood more clearly and to best advantage from the following description of the invention in one of its typical and illustrative forms. Throughout the description reference is had to the accompanying drawings, in which:

Fig. 1 is a general view showing the plug in elevation;

Fig. 2 is an enlarged sectional view showing the upper portion of the plug and its connection with the setting tool;

Fig. 3 is a lower continuation of Fig. 2;

Figs. 4 and 5 are views similar to Figs. 2 and 3, showing the plugparts in changed positions with the slips and packer expanded, and the valve closed;

Fig. 6 shows the positions of the mandrel locking sleeve at the point of releasing the setting tool;

Fig. 7 shows the upper end of the plug with an overshot type retrieving tool applied thereto; f

Figs. 8, 9, and 10 are enlarged cross sections on lines 8 8, 9 9 and Ill-I0, respectivelyl of Fig. 2;

Fig. 11 is an enlarged cross section on line I I--I I of Fig. 2, but omitting a showing of the body of the packer;

Figs. 12 and 13 are views similar to Figs. 1 and 2, illustrating a variational formI o1 the invention:

Fig. 14 shows the locking'mechanism of Fig. 12 in changed position and Fig. 15 is an enlarged section on line I5-I5 of Fig. 12.

Fig. 1 shows the plug, generally indicated at I0, lowered within a well pipe or casing Il on a setting tool I2 which in turnmay be connected to a suitable suspension means, preferably a wire line or cable, not shown. 'Ihe plug may be generally described as comprising circularly arranged pipe gripping means indicated at I3, a, packer' I4, and a valve I5 for controlling the ow of iluid through the plug. As will later appear, while the plug is being lowered within the well pipe, the valve-I5 remains open and the pipe gripping means, I3 and packer I4 remain radially contracted to permit free passage o1' the plug through the pipe. After the plug has been lowered to the setting depth, an upward pull on the suspension means operates to expand the gripping means I3 intor holding engagement with the pipe, also to close valve I5 and expand the packer I fi, and nally to release the setting tool I2 from the plug.

The plug includes amancrel, generallyr indiu rand a pair of diametrically opposite ports I8 which extend through the walls of the section and the corresponding parts of ange IIc.

Passageway Ilb opens to the bore of coupling I'I above barriers I'Iq and hence to the bore of upper mandrel section I6a, so, under certain circurnstances, well fluid may have free passage therethrough, both to act as a relief or discharge port when elements (to be described) are moved longitudinally through the mandrel bore, and to permit the flushing away of sand or other foreign matter which might otherwise lodge Within the mandrel bore.

On the other hand, ports I8 permit Well fluid passing upwardly through the bore I9 of section I6b to by-pass outwardly to the well-pipe as the plug is being lowered therethrough, it being noted that said ports are located above packer I4 so that the established fluid-bypass around the packer permits free movement of the plug down through the well iiuid. Barrier I'Ia acts, of course, to divert the iiuid outwardly through ports I8, rather than into the bore of coupling I'I or mandrel section Ilia, the diverted :fluid acting to wash sand or d'ebris away from slips I3.

It will be noted that mandrel section IGb and the exteriorly exposed part of coupling I I just above the upper end of that section are of less outside diameter than is mandrel section Isa, it

following that the ends of passageway Ilb and ports I8 are unobstructed and the describediluidow therethrough may continue, irrespective of the position to which sleeve 23 (to be later described) may be moved (see, for instance, Fig. 4).

The pipe gripping means I3 preferably comprise circular-ly arranged wedge slips 22 connected with and suspended from what may be termed a body section of the plug, or more specically, a carrier sleeve 23 movable vertically on the upper mandrel section I6a. The slips are suitably attached to the lower end of the carrier sleeve, as by means of links 24 pivotally connected by pins 25 and 26 to lugs 21 and 28 formed integrally with. the slips and carrier sleeve, respectively. The slips 22 are contained .within outwardly inclined, dove tail ways 29 formed in the surface o1' a wedge ring or slips-supporting body 30 that is 'movable vertically with relation to the lower: mandrel section IBb. Upward movement of the slip and carrier sleeve assembly is limited by engagement of the slips with a stop ring or slip-retainer plate 3| having circum ferentially spaced notches 32 receiving the links 24, and attached to the packer supporting ring or anchor plate 33 by anchor bolts 34 (see Fig. 1) extending through the wedge sleeve 30. In turn, upward movement of the stop ring, Wedge sleeve and packer assembly relative to the mandrel, is limited by the engagement of ring 3I with the lower end of coupling-ange I'Ic.

The packer I4 comprises a sleeve 35 of rubber, Neoprene, or other suitable substance, attached to and suspended from ring 33 by suitable means. For instance, packer 35 may be molded about an assembly made up of a metal ring 35a (Fig. 11) upon which the eyes of circumezentially spaced cotter keys 35h are threaded, and the fabric reinforcing strips or hangers 3l, pref-- erably of two plys of. Neoprenedipped cord, which are looped over ring 35a. between the cutter keys in the manner clearly shown in Figs. 2 and 3. The ends of the `cotter keys vproject beyond the upper end of sleeve 35 and are adapted .to be extended through vertical openings 33a in ring 33, said openings` extending upwardly from bottom groove 33h to top groove 33e, these grooves being provided in the horizontal faces of the ring. The sleeve 35 has an annular, upstanding rib 35c which ts in groove 331;, while, after the keys have been thrust through openings 33a, tlie key-legs are spread into groove 33e and tackwelded at 33d to anchor the sleeve assembly to the ring. The sleeve assembly may be replaced, if and when it becomes unduly worn, by breaking away the tack welds and freeing the keys from the ring, -whereupon a new assembly may be substituted.

Thepacker has an upper cylindric bore 38' peripherally engaging mandrel section I8b, and a lower tapered borev 38which receives the correspondingly tapered upper end 40 of the packer expanding sleeve 4|. The latter surrounds mandrel section I6b and is vertically supported by a coil spring 42 received within the sleeve bore 43 and resting on removable ange-ring or retainer 44 at the lower end of the mandrel. The upper end of spring 42 engages the internal downwardly facing shoulder 44a on expander 4I. In the normal position of the parts shown in Figs. 1 to 3, end 40 of the expander sleeve is withdrawn suiliciently from the packer bore 38 to permit the packer to assume its radially contracted condition. Upon upward movement of the mandrel relative to the packer, spring 42, then under compression, thrusts the wedge end 40 of the sleeve into the packer bore, radially expanding the packer and at the same time compressing it longitudinally, so as to bring the packer into sealing engagement with the pipe as shown in Fig. 5. 'Ihe valve means or assembly I5 comprises a Valve cage 4 6 threaded at4'l on the lower end of expander sleeve 4| andv having an internal shoulder 48, between which and the lower end of the sleeve is clamped the valve seat 49. 'I'he valve or stopper 50 has an integral, tubular guideportion extending upwardly through the seat 49, and the valve is urged upwardly toward seating position by a coil spring 52 contained within bore 53 of cage 46. While the plug is being lowered within the Well, the valve is held open in the position of Fig. 3 by engagement of the lower end of the mandrel with the upper end of guide 5|. In this position of the parts, fluid is permitted to flow into the mandrel bore through openings 55 and 56 of the cage and ports 51 through guide 5I, which ports are uncovered when the valve is depressed to open position.

I have provided a locking mechanism which is operable by a straight upward pull of the suspension means and setting tool to automatically lock the slips and packer in gripping and sealing` engagement with the wall of the pipe. An added feature in this same connection is the capacity,

by continued upward pull on the suspension means, for sequentially expanding the slips and packer, closing .the valve, and disconnecting the setting tool from the plug,` all in one simplel and progressive operation.

In its preferred form, the locking mechanism comprises a locking lsleeve 58 inserted within the upper mandrel section I6a and adjustable vertically with relation thereto for'the purpose of connecting and releasing the setting tool from the plug, and also for locking the' mandrel against movement with respect to the carrier sleeve 23 after expansion of the wedge slips and packer. Near its lower end, the locking sleeve 58 is provided with annular surface grooves 59 and 88 adapted to receive detents or llocking elements in the form of steel balls 8| contained within downwardly and outwardly inclined openings 62 drilled through the 'wall of the mandrel. In the position of the parts shown in Fig. 2, balls 6|, be-

ing coniined against outward displacement by z. engagement with the defining wall of the lower bore of the carrier sleeve 23, lock the locking sleeve against upward movement relative to the mandrel The assembly of balls 6I may be considered as both a locking-sleeve latch and as 4an expander latch. Toward its upper end, the locking sleeve is provided with openings 63 containing locking elements or detents in the form of 'steel balls 64 which, when the setting tool is -released, are prevented from dropping into the sleeve bore by a slight reduction in the diameter of openings 63 at the inside of the sleeve, as indicated at 65 in Fig. 8. The assembly of balls 64 may be considered as the setting tool latch.

'I'he setting tool I2 typically may comprise a body 66 having vertically extending guide ribs 61 and a tapered nose spindle' or spear 68 which is adapted to be inserted within the locking sleeve and releasably connected with the plug by the projection of balls 64 'into annular groove 68 in the spindle. A description of the method of engaging the setting tool within the locking sleeve can best be given aftera more complete description of the operation of the locking sleeve and its associated parts. It will suice to note at this point that the setting tool initially is attached to the plug a's shown in Fig. 2, and the plug is lowered within the pipe with the `packer maintained in contracted condition and the valve held open, the lowering being accomplished, for instance, by a cable (not shown) attached to the settingk tool.

In operation, the plug is lowered to the desired depth with the slip and carrier sleeve assembly resting on the wedge ring 30, but without the slips being'in gripping engagement with the pipe and therefore not interfering with the downward progress of the plug by reason of any upward displaceability of the slip and carrier assembly as irregularities on the surface of the pipe are encountered. 1

After the plug has beenlowered to setting position, an upward pull is exerted through the lowering cable on-the setting tool. Since the setting tool is locked to sleeve 58 by balls 64. and the sleeve is locked to mandrel I6 by balls 6 I, this upward pull is transmitted to the mandrel which acts, through spring 42, expander 4I, sleeve 35 andl wedge ring 30, to engage slips 22 with pipe II (it being evident that the slips and carrier are initially free for vertical movement relative to the mandrel and thus to hold the wedge ring, carrier sleeve and packer against further upward bodilyl movement.

Continued upward pull on the lowering cable causes the mandrel to move upwardly through the carrier sleeve 23, wedge ring 30 and the packcause the sleeve toexpand the packer into iiuid tight engagement with the well pipe.

Upward movement of the mandrel continues until balls 6l reach the lower end of an annular recess 10 in the upper portion of the carrier sleeve 23, at which point, see Flg. 4, the balls are displaced out of the mandrel groove into recess 1l| where they overlie shoulder 15 on sleeve 23, thus preventing the mandrel from dropping with relation to sleeve 23, so slips 22 may not be accidentally released. 'I'he displacement of balls Si into recess 1U also permits the locking sleeve 58 to move upwardly with relation to the mandrel. Continued upward movement of the setting tool elevates the locking sleeve to a point at which the relatively shallow annular groove at the lower end of the locking sleeve is brought opposite balls 6I, and balls 64 are raised opposite an annular groove 12 in the carrier sleeve. Upward movement of the locking sleeve beyond this point is prevented by engagement ofv shoulder 13' on the locking sleeve, with the mandrel shoulder 20. With the parts thus brought to the position shown in Fig. 6, balls 64 are displaced radially outwardly within groove 12 to release the setting tool, and at the instant of release, balls 6l are thrust into the shallow mandrel groove 6U but .they still overhang the downwardly inclined bottom surface or shoulder 15 in recess 10 to lock the mandrel against downward movement relative to the carrier sleeve, wedge ring and packer.

The shifting of balls 8| into groove 80 is accomplished by virtue of the camming eiect of the top inclined surfaces B2 (Fig. 6) of openings 82, acting under the influence of spring 42, to displace the balls radially inwardly, said balls thus not only holding the mandrel up with relation to carrier 23 but also holding sleeve 58 from dropping with relation to the mandrel. Thus, after disconnection of thev setting tool, the mandrel remains locked in its upper position with the valve 50 closed and spring 42 compressed to continuously maintain an expanding force against the packer 35. As will be apparent, if for any reason it is desired to maintain downward circulation through the plug, fluid pumped into the pipe Il will ow into the mandrel bore above the packer through openings I8 and, by unseating the valve 5U against the resistance of spring 52, will ow outwardly through ports 51 into the pipe below the packer.

It will be noted that annular clearance exists between sleeve 23 and mandrel section [6b so neither openings I1b'nor I8 are closed oir, even f .though lthe sleeve is relatively depressed. ByA

providing openings 11b and I8 intermediate the ends of the plug and approximately opposite the linkage and ways of the slips, it is assured that l well iiuid will be directed in a manner to iiush the slips and their mountings clear of sand or debris.

It will thus be seen that balls 6I and 64 initially act together to lock certain parts of the mech# anism against relative vertical movement so the upward pull on the setting tool sets the slips, allows the valve to close and expands the packer. Then, at one and the same time, balls 6| are shifted to positions which lock the slips and packer in expanded condition and free the locking sleeve for upward movemena'so upon cone zinued raising movement, balls Bil I to free theA lowering tool from t .tame last movement of the lo it to u jwfitiun where bails (without effecting their slip-and-packer locking function) to hold the locking sleeve in elevatedff position after the lowering tool is freed therefrom.

It will be noted that the lowering tool cannot be freed from the plug until after 'the slips and packer have been locked in fully expandedv and tight engagement with the well pipe, it following that there is no need of auxiliary provisions, usual to most retrievable plugs, to catch the plug in the event of premature release from the lowering line.

The plug may be removed from the well by the use of a retrieving tool of the type shown in Fig. 7, which is operable to release the mandrel from the locking device and thereby permit the mandrel to be returned to its lower position under the influence of spring 42, and also to maintain the wedge slips and carrier sleeve in elevated position relative to the mandrel, while the plug is being removed from the well. The retrieving tool, generally indicated at 16, may be of an overshot type comprising a tubular body 11 connected by a suitable coupling or sub 18 with the lowering cable (not shown). Sub 18 may be provided with iluid passages 19 and 80 communicating with the interior of the body 11. The circulation fluid may thus be discharged downwardly through the body 11, and also outwardly through slots 8| below the sub 18.

The body 11 contains an annular slip carrier 82 attached to wedge slips 83 by integral, depending exible'fingers I4. A coil spring 85 confined between sub 18 and the carrier 82 acts to radially contract the slips by thrusting them downwardly along conical wedge surface 86 at the lower end of the body, downward movement of the slip assembly being limited by engagement of the carrier with stop shoulders 81 on the body. The bottom oi' the body has an outwardly flaring mouth 88 to facilitate centering the tool about the upper end oi the mandrel. vertically extending slots 8l in the body permit insertion of a suitable tool within openings 82a in the carrier 82, for the purpose of releasing the slips after the plug has Vbeen removedirom the well.

In removing the plug from the pipe, the retrieving tool 16' is lowered about the upper end of the mandrel and the carrier sleeve 23, the retrieving tool slip-assembly being upwardly displaceable against the resistance of spring to permit the slips 83 to move down along the out side surface of the carrier sleeve. After the sub 18 has been lowered so its shoulder 18 is in engagement with the 'upper end of the locking sleeve 58 (the latter being in the position shown in Fig. 6) a light downward blow against the locking sleeve, applied for example by operation of a jar carried on the lowering cable above the sub 18, will displace balls 8l outwardly within recess 10 and return the locking sleeve to the position of Fig. 2 in which balls 6l enter the groove 5S to release the mandrel for downward movepacker being contracted about the mandrel.

When released, the mandrel is returned by spring d?. to its lowermost position, opening the valve El) relieving the spring thrust against the WNng sleeve.

to open valve in the manner ice in that it becomes the plug from 'the pipe even though the pressure above and belowA the plug are not balanced. Consequently, it generally is unnecessary to run water into the pipe for the purpose of balancing pressures above and below the plug.- The relatively small cross-sectional area of the valve with respect to the cross sectional area'of' the bore of pipe Il, makes it comparatively easy to open the valve even against relatively high pressures below the plug. The

engagement of slips 83 with the carrier sleeve re` tal-ns the mandrel in its valve opening position so that the valve is held open against high pressures and fluid ilow may continue through the plug until the pressures above and below are in balance. A nal jar upon the mandrel drives the slip expanding ring 30 downward and relieves slips 22 from wedging engagement'with the pipe, slips 88 having been set by wedge face 86 in gripping engagement with sleeve 23. The plug may now be removed from the well by elevating the retrieving tool, slips 22 being raised into engagement with the stop ring 3| and maintained in contracted condition.

It will be noted that since the plug is elevated through the slips kcarrier and ring 8| (rather than through a pull exerted directly on the mandrei) there is no relative vertical movement between the mandrel and packer during the pickup operation and therefore no tendency for the packer (if, accidentally, it frictionally engages` the pipe) to be dragged down overl-the largerv diameter of lthe expanding member with a consequent danger of wedging the packer outwardly against the walls of the pipe.

It will also be noted that the slips 22 are forcibly moved to their contracted positions before the upward draft on the plug, proper, is applied, and, as the plug is being lifted,I the carrier 28 and mandrel I5 are locked in such rel-ative positions that slips 22 are also locked against accidental movement to expanded or pipe-engaging .l

positions. 4 The setting tool I2 may be attached to the plug byirst latchingv (with balls 5|) the locking sleeve `5s in its upper position vof Fig. s. This' may be done by holding the carrier-sleeve 23v stationary and pulling out the locking sleeve by means of a handle through holes in its upper end. The spindle end |i8'` of the lowering tool is then inserted in the bore of sleeve 58, balls 64 being cammed radially outward into groove 12 to permit the spindle to be depressed to a position where groove 68 linesup with those balls, and shoulder 68a of the setting tool engages the upper end of sleeve 58. Av blow struck on the head of the lowering ltool then drives sleeve 58 downward with relation to mandrel section IBa,

this movementshifting balls 84 into locking as- Since groove 80 is vrelatively shallow, the balls 8| are cammed radially outward from that groove and more fully into recess 10, to allow the described downward movement of the locking sleeve.

The downward movement of the sleeve lines up relatively deep groove 58 with balls-8| so the latter may move to the position of Fig. 2, thus unlocking sleeve 58 Afrom carrier 23, whereupon spring 42 is free to shirt au parts to the posi: tions of Fig. 2.

It is desirable to re-set the plug at a lower depth. particularly in locating leaks in well pipe. where the plug is successively set at lower depths with a test made between each setting. Ordinarily, this has required that the plug be fished4 from thehole after each test, 17e-conwalls ofthe pipe.

Assume the plug has been set ,and is in the condition of Fig. 6, except that the lowering tool has been entirely removed.4 It will be remembered that balls 8| are'no'w holding sleeve 58 in the elevated position (with relation to mandrel |8) shown inlthis gure. so it is assured groove 'l2 is lined up with balls 54. v. l

The setting tool |2 is then run in on a weighted lowering line, the conical nose 88a guiding spindie 58 into the bore of locking sleeve 58. Shoulder ,68a strikes theupper end of sleeve 58 with suieient force to drive it down. .lust as described immediately above in connection with the outof-well ,attachment of the tool. With the iowerlng'l tool thus connected to the locking sleeve by balls 84 and with balls 8| lined'up with groove 58 (the parts would then be approximately in the position of Fig. 4. but the groove 58 would be somewhat lower than there shown) balls 8| are free to clear shoulder 15, and spring 42, aided by`gravity, is free to. move .the m-andrel downwardly through sleeve 58, opening valve l5, en- 89.81118 Bange .'|c with ring 3] and allowing the packer to contract. A continuation of the downward force imposedl on sleeve 58 engages the lower` end of the sleeve with the upper end Il of coupling I1, thus jarringmandrel I6 downwardly, which, through flange llc and ring 3|,

drives wedge ring 80 down, the latter, due to the p dove-tail ways 28, thus radially contracting the slips assembly |3 and freeing the plugfrom the All parts will now be in the condition of Figs. 2 and 3. it following that the plug may be lowered to a new depth, reset, and then freed from the lowering tool, all as has been previously ,described. This sequence of resetting at successively lower depths may be repeated asoften as the depth oi the well will allow. l

Figs. 12 to 15 show a variational form of the invention similar in general scribed embodiment, but differing prncipallyin the omission of the valve, and certain changes in the parts that permit substantial reduction-in the required length of the plug. Here the mandrel comprises upper and lower relatively longitudinally movable sections 8| and 82 having a lost motion connection by way of bolt 83 extendto the previously deby a tubular coupling 85 having ports 86 commuv nicating with the mandrel bore 81. As inthe first described form of the'inventiom the slip expanding wedge l NJtied together by bolts |00 extending through the stop ring |0| and sleeve packer supporting ring |02.l 'Ihe packer sleeve |08, the upper end of which is received within .the tapered portion |84 of the packer bore. As will be understood. the'packer is radially expansible and contractibie by upward and downward movement, respectively, of the lower mandrel section and wedge member |08 within the wedge sleeve and packer assembly. f

Theslip carrier sleeve |01 is vertically movable on the upper mandrel section 8|, and is attached 88 and threaded into the its iowerend the upwardly tapered tubular packer expanding wedgev sleeve 88 and packer 88 are is internally reenrorced and attached to the ring 9 .to the slips |08 by the pivoted links |09. The

slips are adapted to slide through dove-tail ways in member 90. The locking sleeve ||0 contained within the upper mandrel section bore normally is releasably held against upward movement relative to the mandrel by detents engaging the locking sleeve shoulder ||2, the de- `tents being formed by vertically slotting the upper end of the mandrel at suitable circularly spaced intervals, which gives the detents a desired degree of radial resilience. `'I'he mandrel and locking sleeve are releasably interlocked in their normal positions of Fig. 12 by circumferentially arranged balls ||3 contained within-openings ||4 in the mandrel and rprojecting into an annular recess ||5 in the locking sleeve. 'I'he ca-rrier sleeve |01 is provided with a series of vertically spaced, `internal annular grooves ||6 adapted to receive the balls ||0 to prevent downward movement of the mandrel relative to the locking sleeve under conditions later described. The setting tool ||1 is releasably locked within sleeve ||0 by balls I I8 (corresponding to balls 64 in Fig. 2) contained within openings ||9 in the locking sleeve and projecting within the recessed portion |20 of the setting tool.A

In operation, the plug is lowered on the suspension cable with the parts positioned as shown in Figs. 12 and 13. When the desired depth has been reached. an upward pull on the setting tool rst y -locking sleeve ||0 to accommodate possible upcauses the wedge sleeve 90 to bring the slips |00 into gripping engagement with the pipe. Continued upward pull, transmitted to the lower mandrel section by the engagement of bushing 90 with the head 93a of bolt 99, causes the wedge member |03 to expand the packer sleeve into fluid tight engagement with the casing. During this time, the upper mandrel section 9| will have become raised within the carrier sleeve a distance depending upon the length ofmandrel travel re' Y quired to fully expand the packer.

At the 'point at which further upward movement of the mandrel is prevented by the engagement of the wedge member |03 within the packer, the pull on the locking sleeve ||0 overcomes the resistance of detents causing shoulder 2 to be pulled upwardly past the detents to the point at which they spring back into the annular groove 2| in the locking sleeve. Upward movement oi the locking sleeve within the mandrel during this operation, is limited by engagement of the sleeve shoulder |29 with shoulder |20 at the upper en'd of the counterbore |21. As a result of such upward movement of the locking sleeve. balls ||0 are displaced outwardly within `the particular carrier sleeve groove H6 opposite which they happen to be positioned, and balls H0 are moved upwardly to the point of outward displacement -into recess |20, releasing the setting tool ||1, see Fig. 14. Immediately upon release of the setting tool, balls ||0 lock the mandrel against downward movement relative tothe slip carrier, wedge sleeve and packer, by reason of the balls being retained within the groove |0a by engagement within the recessed portion |20 ot the locking sleeve. lBy seating the bailswithin the relatively shallow recess |20, the. locking sleeve is prevented from becoming accidentally moved downward to the point of releasing the mandrel. The plug may be removed from the well by an overshot type retrieving tool as previously described. By lowering .the retrieving'tool around and into engagement with the upper end of the letting sleeve, positioned as shown in Fig. 14, and then jarring down on the retrievhig tool,

shoulder |2 is returned past the detents` to the position of Fig. l2; in which the locking sleeve will be moved downward to the point of accommodating balls ||0 within recess ||5, thereby releasing the balls from locking engagement with the carrier sleeve. 'I'he upper mandrel section is jarred downward to the point of engaging bushing 04 with shoulder 95a formed by the `upper end of coupling 95, with the result that the lower'mandrel section is driven downward sufciently to permit contraction of the packer 99 to releasing position. With the over-shot slips now engaging the carrier sleeve |01, the plug may be removed from the well, the slips |00 being raised into contracted position and into engagement with the ring |0|, which in turn, engages the coupling shoulder 95h to support and elevate the mandrel assembly.

The lost motion connection between the mandrel sections permits upward movement of the lower section and expansion of the packer after the plug has been set in the well, without in any way interfering with the upper section and 1ocking sleeve assembly. Thus, should increased'well pressure tend to force the lower mandrel section upwardly and thus more tightly expand. the packer, bolt 93 will move upward within bushing 90 without producing movement of the upper mandrel section, suilicient space being provided between the bolt head 92a and the lower end of the ward movement of the lower mandrel section.

Well fluid flowing upwardly through the mandrel bore 91 is discharged outwardly through openings 96 and upwardly around the carrier sleeve |01. This feature of maintaining upward flow around the carrier sleeve is of importance in that the well ilow washes away and removes from the annular space |30 between the carrier sleeve and well pipe, sand or other solid particles that otherwise might accumulate therein andobstruct lowering the retrieving tool down about the carrier sleeve. Here the well iluid continuously washes the space |30 above openings 90, free from settling sands.

Another important feature of the inventionis the adaptability of the lower mandrel section 92 for replacement by other mandrel sections having diierent bore diameters. In addition to its function as a mandrel, section 92 may also serve as a choke for restricting the flow of well fluid through the plug, the degree to which the uid is restricted being determined by the size of the mandrel bore 91. In case it is desired to restrict iiow through the plug to a greater or lesser degree, the lower mandrel section 92 may be disconnected from coupling!! and wedge member |00, and replaced by another section having a larger or smaller size bore. as the case may be.

I claim: l,

1.In a plug adapted to be lowered in a well pipe on suspension means, the combination com-f prising relatively vertically movable body and mandrel sections, a packer encircling the mandrel section and being expansible into `tight engagement with said pipe, a verticallyV slidable packer expander supported on the mandrel and engaging the packer, a spring engaging and adapted to exert packer-expanding force against said packer expander, means whereby relative. vertical movement o! said. sections in one direc-d w spring acting between the mandrel and wedge member and adapted to exert `a packer expanding force against said wedge member, and means whereby relative movement of said sectionsin one direction compresses the spring and, through the packer expander, expands the packer.

3. In a plug adapted to be lowered in awell pipe on a suspensionv means, the combination comprising a mandrel, a carrier sleeve mounted directly on and movable vertically along the mandrel, pipe gripping means suspended from said sleeve, a packer encircling the mandrel, both said gripping means'and packer being expansible into tight engagement with the pipe by upward `movement ofthe mandrel within the sleeve. and

means inside said sleeve forreleasably locking the mandrel against downward movement relative to the carrier sleeve after expansionof the gripping means and packer.

4. In a plug adapted to be lowered in a well pipe on aY suspension means, the combination comprising a mandrel having a tubular portion, a carrier sleeve movable vertically on the mandrel, pipe gripping Ameans suspended from said sleeve, a packer encircling the mandrel. both said gripping means Iand packer being expansible into tight .engagement with the pipe by upward movement of the mandrel within the sleeve, and means'including a locking sleeve movable vertically within the bore of the tubular portionof said mandrel for releasably locking the mandrel against downward movement relative to the carrier sleeve after expansion of -the gripping means and packer.y

5. The combination including a plug adapted to be lowered in a well pipe on a suspension means, said plug including a vertically movable member, pipe gripping means on'said plug and expansible into gripping position by upward movement of said member; a setting tool carried by said suspension means and inserted within a bore in the upper end of said member, latch means within said bore and releasably connecting said setting tool and member, and a lock for said latch means, all in a manner whereby upward movement of the suspension means ilrst expands the grippingmeans and subsequently releases said lock and actuates the latch torelease the setting tool from said member.

6. The combination comprising a plug adapted to b lowered. in a well pipe on a suspension means, said plug including a mandrel, a carrier sleeve movable vertically on the mandrel,

wedge slips suspended from said sleeve, a slip expanding wedge ring on the mandrel, a packer on the mandrel below said wedge ring. means connecting'said ring and packer and holding them against relative bodily movement, a packer expanding sleeve on the mandrel below the packer,

the mandrel being vertically movable relative to said wedge ring, packer and the packer expanding sleeve, a pair of vertically spaced, opposed shoulders, one on the mandrel and the other on the last mentioned sleeve, and a spring about the mandrel and extending between said shoulders movement, a

whereby upward movement of the mandrel causes 7. The combination comprising a plug adapted to be lowered in a well pipe on a suspension means, said plug including a mandrel containing a ud passage, a carrier sleeve movable vertically on the mandrel, wedge slips Suspended from said sleeve, a slipl expandingv wedge ring on the mandrel, a packer on said wedge ring, means connecting said ring and packer and holding them against relative bodily packer expanding sleeve on the mandrel below the packer, the mandrel being vertically movable relativeto said wedge ring,

packer and the packer expanding sleeve, apair of vertically spaced, opposed shoulders, one on the mandrel and the other on the last mentioned sleeve, and a spring about-the mandrel and extending between said shoulders whereby upward movement of lthe mandrel causes the spring to exert an expanding force against the packer, a spring loaded packer expanding sleeve, and means on the mandrel adapted releasably to hold the valve open 20 against its spring-load.

` 8. The combination comprising a plug adapted to be lowered in a well pipe on a suspension means, said plug including a mandrel, a carrier sleeve movable vertically on the mandrel, wedge .slips suspended from said sleeve, a slip expanding wedge ring on the mandrel, a packer on the mandrel below said wedge ring, means connecting said ring and packer and holding them l against relative bodily movement, a packer` expanding sleeve on the mandrel below the packer, the mandrel being vertically movable relative to said wedge ring, packer and the packer expanding sleeve, a pair of vertically spaced, -opposedl shoulders, one on the mandrel and the other i0 on the last mentioned. sleeve, a spring about the mandrel and extending between said shoulders whereby upward movement of the mandrel causes the spring to exert an expanding force against the packer,

the mandrel against downward movement rela:

- tive to the carrierV sleeve.

9. In well pipe plug, a mandrel comprising upper and lower sections, pipe gripping means associated with the mandrel `and expansible into V holding engagement with the well pipe by upward movement of the mandrel with respect thereto, a carrier forsaid gripping means movable vertically .onthe upper section of the mandrel, a packer carried by the lower mandrel section, there being.

a well-iluid passage through .the lower mandrel section and opening to the exterior of the plug at a point below the packer and at a point near the lower end of the carrier but above the packer.

l0. In well pipe plug, a mandrel comprising up- 6o per and lower relatively vertically movable sections, pipe gripping means associated with'v the mandrel and expansible into holding engagement with the well pipe by upward movement of the mandrel with-respect thereto, ay carrier flor said the upper gripping means movable :vertically on section of the mandrel, a packer carred by the lower mandrel section, therebeing a well-uid 4passage through the lower mandrel section and opening to the exterior of the plugat a point below the packerA and at a point near the lower end of .the carrier but above thepacker.

1l. lIn well pipe plug, a mandrel comprising an upper and lower relatively vertically movable section, pipe gripping vmeans associated with the the mandrel below 10 valve carried by said and means for releasably locking 45 against relative mandrel and expansible into holding engagement with the well pipe by upward movement oi' the mandrel with respect thereto, a carrier connected to said slipping means and movable vertically on the upper section oi' the mandrel. a packer carried by the lower mandrel section, there being a well-fluid passage through the lower mandrel section and opening to the exterior of the plug at a point below the packer and at, a point near the lower end of the carrier but above the packer,said lower mandrel section being movable upwardly relative to the upper mandrel section by well pressure to cause the packer to expand.

l2. In well pipe plug, a mandrel comprising upper and lower sections, pipe gripping means associated with the mandrel andexpansible into holding engagement with the well pipe by-upward movement of the mandrel with respect thereto, a carrier for said gripping means movable vertically on the upper section of the mandrel, a packer carried by the lower mandrel section, said lower mandrel section having an open iiuid passing bore for passing well iluid upwardly through the plug past the packer, and means detachably connecting said mandrel sections whereby the lower section may be replaced by a section of diii'erent bore size..

13. In well pipe plug, a mandrel comprising upper and lower sections, pipe .gripping means associated with the mandrel and expansible into holding engagement with the well pipe'by upward movement oi the mandrel with respect thereto, a carrier for said gripping means movablevertically on the upper section of carried by the lower mandrel section, said lower mandrel section having an open iluid passing bore opening at its lower end to the exterior oi' the plug for passing well iiuid upwardly through the plug-past the packer, there being a side port in the lower mandrel section near its upper end for discharging iiuid from said bore through the side of the mandrel at a point intermediate its ends' and above the packer, and means detachably connecting said mandrel sections whereby the lower section may be different bore size.

14. In well pipe plug, a mandrel comprising upper and lower sections, pipe gripping means associated with the mandrel andexpansible into holding engagement with the wellpipe by upward movement oi' the mandrel with respect thereto, a carrier forsaid gripping means movable vertically on the upper section of the mandrel, a packer carried by the lowermandrel section, and there being a passage through the lower mandrel section and through which'well liquid ows upwardly within the lower mandrel section and is discharged into the well pipe through an opening in the side of the mandrel at a point above the packer, and a barrier-in' the e above the opening and adapted to divert ilui flow through said opening. Y v

.15. The combination comprising a setting tool adapted to be lowered in a well pipe on a suspension means, a plugincluding relatively vertically movable body and mandrel sections, a releasable connection between the setting tool and oneoi the sections, pipe rippina means expansible into holding engagement with the pipe -by relative vertical movement oi said sections in one direction, means for locking said sections movement in an opposite direction after expansion 'o f'said gripping means and means positively locking said releasable connection until said sections have been locked.

the mandrel, a packerreplaced by a section oiV tically movable body 16. The combination comprising a setting tool adapted to be lowered in a well pipe on a suspension means, a plug including relatively vertically movable body and mandrel sections, a releasable connection between the setting tool and one of the sections, pipe gripping means expansibleginto holding engagement with the pipe byl relative vertical movement of said sections in one direction, means for locking said sections against relative movement in an opposite direction `after expansion of saidgripping means, means'positively locking said releasable connection until said sections have means acting to release said last mentioned locking means and to tree the setting tool from said one section upon upward movement of the setting tool after said sections have been locked.

17. The combination comprising .a setting tool adapted to be lowered in a well pipe on a suspension means, a plug including relatively verand mandrel sections, a releasable connection between the setting tool and one o1' the sections, pipe gripping means expansible into holding'en'gagement with the pipe by relative vertical movement of said sections in one direction, means for locking said sections against relative movement in an opposite direction after expansion of said gripping means, means positively locking said releasable connection until said sections have been locked, and means acting to release said last mentioned locking means and to free the setting tool from said one section upon upward movement of the setting tool after said sections have been locked; said setting tool being subsequently re-engageable with said one section, while the plug is still in the pipe, to restore the releasable connection, and to unlock the sections, all'by a direct lowering movement or the suspension means.

18. The combination comprising a setting tool adapted to be lowered in a well pipe on a suspension means, a Plug including relatively vertically movable body and mandrel sections, a releasable connection between the setting tool and one of the sections, pipe gripping means expansible into holding engagement with the pipe by relative vertical movement of said sections in one direction, means for locking said sections against relative movement in an opposite direction after expansion oi' said gripping means, means positively lock` Y ing said releasable connection until said sections ing movement of the suspension l connection between the setting tool .have been'locked;

have been locked, andmeans acting to release said last mentioned locking means and to free the setting tool from said one section upon' upward movement oi the setting tool alter said sections said setting tool being subsesaid one section, while to restore the releasthe sections, and to all by a direct lowermeans.

19. 'I'he combination comprising a settingtool adapted to be lowered in a well pipe on a suspension means, a plug including relatively vertically movable body and mandrel sections. a` releasable and one of the sections, a packer expansible into holding engagement with the pipe by relative vertical movement oi' said sections in one direction, means for locking quently re-engageable with the plug is still in the pipe, able connection, to unlock release the grippins means.

and means positively locking nection until said sections have been locked.

20. The combination comprising a setting tool adapted to be lowered in a well pipe on a suspenbeen locked, and

sion means, a plug including relatively vertically movable body and mandrel sections, a releasable connection between the setting tool and one of the sections, a packer expansible into holding engagement with the pipe by relative vertical movement of said sections in one direction, means for locking said sections against relative movement in an opposite direction after expansion of said packer, means positively locking said releasable connection until said sections have been locked, and means acting to release said last mentioned locking means and to free the setting tool from said one section upon upward movement of the setting tool after said sections have been locked.

21. 'I'he combination comprising a setting tool adapted to be lowered in a well pipe on a suspension means, a plug including relatively vertically movable body and mandrel sections, a releasable connection between the setting tool and one of the.

sections, a packer expansible into holding engagement with the pipe by relative vertical movement of said sections in one direction, means for locking said sections against relative movement in an opposite direction after expansion of said packer, means positively locking said releasable connection until said sections have been locked, and means acting to release said last mentioned locking means andto free the lsetting tool from said one section upon upward movement of the setting tool after said sections have been locked; said setting tool being subsequently re-engageable with said one section, while the plug is still in the pipe, to restore the releasable connection and to unlock the sections, and to release the packer all by a directlowering movement of the suspension means.

22. The combination comprising a setting tool adapted to be lowered in a well pipe on a suspension means, a plug embodying a pair of members associated in a manner adapting them for relative vertical movement, pipe gripping means and a packer associated with said members and adapted to be operated into and out of tight engagementwith said pipe by virtue of relative vertical movement of said members in opposite directions, a locking element associated with said members and movable, at times, vertically with respect thereto, a pair of i latches,.one acting between the lowering tool and saidel'ement, and the other acting between said element and, at times, both said members, said latches initially locking the lowering tool and one of said members against relative vertical movement whereby, after the plug is lowered to a predetermined position, the raising of the lowering tool sets up relative vertical movement of the members in a direction to operate the gripping means and packer into tight engagement with the pipe, means effective by continued upward movement of the lowering tool to operate said other latch to lock the members against opposite relative movement and to release said locking element whereby it is moved, by a continuation of the upward movement of the lowering means, to a position releasing said one latch, all in a manner whereby a continued upward movement of the lowering tool lifts the lowering tool clear of the plug.

23. The combination comprising a setting tool adaptedA to be lowered in a well pipe on a suspension means, a plug embodying a pair of members associated in a manner adapting them for relative. vertical movement, pipe gripping means anda packer associated with said Amembers and adapted to.be operated into and out of tight engagement with said pipe by virtue of relative vertical movement of said members in opposite directions, a locking element associated with said members and movable, at times, vertically with respect thereto, a pair of latches, one acting between the lowering tool and said element, and the other acting between said element and, at times, both said members, said latches initially locking the lowering tool and one of said members against relative vertical movement whereby,

' after the plug is lowered to a predetermined position, the raising of the lowering tool setsup relative vertical movement of the members in a direction to operate the gripping means and packer into tight engagement with the pipe, means Veffective bycontinued upward movement of the lowering tool to operate said other latch -to lock the members against opposite relative movement and to release said locking element whereby'it is moved, by a continuation of the upward movemen-t of the lowering means, to a position releasing said one latch, all in a manner whereby a continued upward movement of the lowering tool lifts the lowering tool clear of the plug, said other latch, when it is in member-holding position, engaging said element and holding it releasably in its last mentioned position.

24. The combination comprising a setting with said members and movable', at times, vertically with respect thereto, a pair of latches,

one acting between the lowering tool and said element, and the other acting between said elenient and, at times, both said members, said latches initially locking the lowering tool and one of said members'against relative vertical movement whereby, after the plug is lowered to a predetermined position, the raising of the lowering tool sets up relative vertical movement of the members in a direction to operate the gripping means and packer into tight engagement with the pipe, means eiective'by continued upward movement of the lowering tool to operate said other latch to lock the members against opposite relative movement and to release said locking element whereby it is moved, by a continuation of the upward movement of the lowering means, to' a position releasing said one latch, all in a manner whereby a continued upward movement of the lowering tool lifts the loweringtool clear of the plug; said lowering tool being subsequently re-engageable with the plug while it remains in the pipe to successively move said latching element downwardly to relock said one latch, release said other latch, set up relative vertical movement between the members in an opposite direction to free the gripping means and packer from the pipe, and relock said other latch. 25. In a well pipeplug, a mandrel, pipe gripping means associated with the mandrel intermediate the ends thereof, said means being expansible into holding engagement with the pipe by vertical movement of the mandrel with respect thereto, there being a well iiuid passage in said mandrel and opening to one end thereof, and there being an opening from said passage to the exterior of the plug at a point adjacent said gripping means.

gripping means, there being a well fluid passage in said mandrel opening to the exterior of the plug at a point below the packer and at a point adjacent said gripping means and above the packer.

GRANVILLE S. KNOX. 

